The present invention is related to a sensor system and a measuring method thereof, and more particularly, to a sensor system of a surface plasmon resonance (SPR) for analyzing a characteristic of a substance and a measuring method thereof.
At present, the biological chip is developing vigorously in the academic community, the government, and the private institute in many countries. In respect of DNA chips, many technologies are getting on for maturation, such as the DNA combination analysis, the DNA sequencing, the DNA quantification analysis, the capillary electrophoresis separation detection, the nucleic acid magnification, and the parallel gene expression analysis. Meantime, a series of analyzing methods are derived from these technologies, for instance, the cell separation, the cellular immunity analysis, and the high throughput screening combined with combinatorial chemistry for the first screening of new medicine research. In respect of material, except processing the chip by using the silicon, the plastic molding technology and the plastic body are beginning to be used for processing the biological chip. Nowadays, the three steps of sample handling, chemical reaction, and detection have been integrated partially. Only that the complete integration needs more time, but not so far to get it accomplished. One thing we should pay attention is that the development of biological chip still focuses on the application of DNA chips so far. A series of technologies and products have been developed in the light of the detection requirements for DNA, such as the DNA rapid detection analyzing technology and the product thereof, DNA replication and the segment analyzing technology and the product thereof, and the integrated DNA analyzing system. However, in the aspect of protein chip research, it has not been either largely invested or accomplished. Therefore, a wide research space and the opportunities are left and very suitable as a purpose of biotechnology industry development.
In the present protein research, there is a field called proteomics. This field emphasizes on how to proceed the research at the proteinic level of receptor and hormone in large scale so that the important function, such as the disease mechanism, the cellular operation mechanism, and the cellular net work signal, can be fully understood. These work will offer positive assistance for the development of new medicine, especially the medicine related to protein action within a cell. At present, the choke point of these work is the large consuming of manpower and time. For example, it needs continuous work for 1-8 hours in average, and 1000 protein molecules are required at least for the detection and the analysis. From this, it is not difficult to tell the difficulties and the wide range of this job. It can hardly be accomplished in a short term by the present technology. Hence, a system of protein biomedical chip established by the Micro-Electro-Mechanical System (MEMS) is needed for proceeding the research contributive to the protein level research including the protein structure optimum. Hoping that there will be breakthrough in the direction of medicine designing, medicine screening, new receptor, molecular structure, and intelligent macromolecule element.
At present, a brand-new technology has been provided to this field because of the maturation of the semi-conductor manufacturing technology. A further development for the sensor system has been provided by the Micro-Electro-Mechanical System (MEMS). In addition, the potential in biomedical detection provides a wide market for the Micro-Electro-Mechanical System. Presently, the product, which combines the technologies from different fields including semi-conductor technology, molecular biology, macromolecule material, artificial intelligence, and system integration, has been entered clinical trial from lab experiment. Among the researches full of new ideas, the microarray technology combined with genetic engineering has been applied to the research of gene chips. Many achievements have been made right now and reached the commercialized state. Take xcexc Total Analytic System (xcexcTAS) in the microarray development at the moment as an example, 100-1000 dots within 1 xcexcm2 workable for detection. By cooperating with the xcexc capillary electrophoresis, the sample can be fast loaded automatically by the manipulator system, so that the separation length is decreased within 5 cm and the separation can be finished within 1 second. If parallel processing is cooperated as well, then the requirements of distant detection and immediate analysis in medicine development are able to rapidly achieved. At present application of protein chips, the detection and analysis of 1024 samples containing lesser than 500 ng can be finished within 3 hours. After the genomic project is claimed finished, the need for the detection of protein function keeps growing and every country is widely developing the protein chip.
The surface plasmon resonance (SPR) phenomenon is an optical method being widely applied to detect the properties of surfaces and interfaces. It is first discovered by physicists and applied to study the properties of metals and dielectric thin films. Afterwards, chemists applied it to study metal/solution interface and Langmuir-Blodgett (LB) thin film. The surface plasmon resonance (SPR) device can display immediate and highly-sensitive detection of biological mutual interaction. It is therefore widely applied to biochemistry research. The surface plasmon can be excited in metal or semi-conductor interface by light energy, electricity energy, mechanical energy, and chemistry energy. The effect of plasmon excitation can be detected by the reflective intensity change when the light incident angle or the wavelength change. However, both the light incident angle and the incident wavelength can only be analyzed two-dimensionally. As to three-dimensional analysis, it is still under researching process and the design mostly focuses on thickness detection. So far, there is no report related to the design with the function for detecting uneven depth, especially the design with the function for detecting different depth of biological molecule which is attached on the chip. It is just the characteristic of the present invention which will be described below.
It is an object of the present invention to provide a protein chip which can analyze biological molecule immediately.
It is another object of the present invention to provide a biological detection chip which detects sample three-dimensionally by surface plasmon resonance (SPR).
It is another object of the present invention to provide a sensor system of a surface plasmon resonance (SPR) for analyzing a characteristic of a substance, wherein the differences of the penetrated depth of samples are measured and analyzed by the spectrograph analyzer within the wavelength range of both visible light and near infrared light.
According to the present invention, a sensor system of a surface plasmon resonance (SPR) for analyzing a characteristic of a substance, comprises: an optical device for generating a first light beam and a second light beam in sequence; a sensor device mounted between a first dielectric layer and a second dielectric layer for respectively generating a first plasmon wave and a second plasmon wave in response to an optical characteristic change of the first light beam and the second light beam with respective to the substance, wherein the substance is disposed between the sensor device and the second dielectric layer, and a resonance is generated from the first plasmon wave and the second plasmon wave respectively generating a first reflective signal and a second reflective signal in response to a refractive index difference between the first dielectric layer and the second dielectric layer; and a measuring device for measuring spectra of the first reflective signal and the second reflective signal and obtaining a measured value, wherein the measured value is substituted into an operational formula to calculate a reference value used for analyzing the characteristic of the substance.
In accordance with the present invention, the substance is a biological molecule.
Preferably, the substance has a penetrated depth ranged from 1-2500 nm.
Preferably, the first light beam and the second light beam have different wavelengths.
Preferably, the optical device further comprises: a light source for generating the first light beam and the second light beam; a polarizer for polarizing the first light beam and the second light beam and generating a polarized first light beam and a polarized second light beam; plural lens for focusing the polarized first light beam and the polarized second light beam inside an optical fiber so as to allow the polarized first light beam and the polarized second light beam to enter the optical fiber and travel therethrough; and a splitter connecting the optical fiber and a spectrometer, wherein the spectrometer is used for analyzing a spectrum change of the first reflective signal and the second reflective signal generated upon the resonance.
Preferably, the first light beam and the second light beam are respectively visible light and near infrared light, wherein the visible light has a wavelength ranged from 400-700 nm and the near infrared light has a wavelength ranged from 700-1500 nm.
Preferably, the sensor device is one of a surface plasmon resonance (SPR) optical fiber sensor and a surface plasmon resonance (SPR) chip sensor.
Preferably, the sensor device is one of a surface plasmon resonance (SPR) optical fiber sensor and a surface plasmon resonance (SPR) chip sensor.
Preferably, the sensor device further comprises: a multi-layer structure; and a coupler for coupling the first light beam and the second light beam to the multi-layer structure.
Preferably, the multi-layer structure further comprises a multimode metal layer, a biomedical linker layer and a biomedical ligand layer in sequence.
Preferably, the multimode metal layer has a thickness ranged from 10-300 nm.
Preferably, the multimode metal layer is composed of plural metal layers with different thicknesses.
Preferably, the multimode metal layer is composed of plural metal layers made of different materials.
Preferably, the substance is attached on the surface of the multimode metal layer.
Preferably, the first light beam and the second light beam are incident upon the second dielectric layer through the first dielectric layer.
Preferably, the first dielectric layer has a refractive index larger than that of the second dielectric layer.
Preferably, the measuring device includes a hardware device and a software device.
Preferably, the hardware device is a spectrometer for measuring the measured value and the software device is a digital signal processing program.
Preferably, the spectra of the first reflective signal and the second reflective signal have the measured value including a site, a width, and a penetrating depth.
Preferably, the operational formula is a specific equation using a least square curvilinearly coordinating spectra of the first reflective signal and the second reflective signal to obtain the reference value.
Preferably, the reference value includes a refractive index, a light-eliminating factor, and a thickness.
According to another aspect of the present invention, a measuring method of a surface plasmon resonance (SPR) system for analyzing a characteristic of a substance, comprising steps of: (a) providing a first light beam and a second light beam; (b) providing a sensor device for respectively generating a first plasmon wave and a second plasmon wave in response to an optical characteristic change of the first light beam and the second light beam with respect to the substance; (c) generating a resonance from the first plasmon wave and the second plasmon wave respectively generating a first reflective signal and a second reflective signal in response to a refractive index difference between a first dielectric layer and a second dielectric layer; and (d) measuring spectra of the first reflective signal and the second reflective signal and obtaining a measured value, wherein the measured value is substituted into an operational formula to calculate a reference value used for analyzing the characteristic of the substance.
In accordance with the present invention, the first light beam and the second light beam are provided from an optical device.
In accordance with the present invention, the measured value is obtained from a spectrometer.